I can tell you about the detroit ones themselves. there are three land based ones plus one right across the river in windsor. so really four within a short drive.

Easy to find? must be. I didn't get lost.. and I get lost crossing the street. In fact Windsor (in Ontario) is right on the main street near the tunnel, then once you are out of the tunnel its easy to get to Greektown. From there to Motor City and MGM are a 15 minute drive.

You can hit all in a few hours - except possibly for the traffic into and out of Canada.